1. Field of the Invention
The present invention relates to a bowling ball and method to drill the thumb and finger holes in the same, and more particularly a bowling ball having a new weight block, indicia on the surface of the ball to locate the weight block and a method to drill the thumb and finger holes in relationship to the weight block.
2. Description of the Prior
Various weight blocks are known for redistributing top weight of a bowling ball primarily to offset the loss in weight resulting from drilling the thumb and finger holes. However, none of them provide an elongate weight block along and near the surface of the ball and having another elongate section extending generally transverse from the weight block from an intermediate portion of the weight block and extending toward the center of the ball. This shape and positioning of the weight provides desired breaking of the bowling ball as it rolls down the lane with using relatively localized weighting and, at the same time, maintaining relatively dynamic stable characteristics.
In U.S. Pat. No. 4,121,828 issued Oct. 24, 1978, to Amburgey, one of the weight block configurations is a segment of an annular disk in which the minor diameter of the segment is preferably closer to the surface of the ball than the center. This structure does not have an elongate section depending transverse from an intermediate portion of the segment of the annular disk. Other configurations, as in U.S. Pat. No. 4,286,034, issued May 19, 1981, to MacDonald, are weight blocks preferably in the shape of a segment of a circle or relatively symmetrical members such as a cube or truncated cone. None of these weight structures provide an elongated structure near the surface of the ball having an elongate structure extending transverse to an intermediate portion of the elongated structure nearer the surface.
Various bowling balls having weighting systems include indicia on the outside of the ball to show the center of the weight and the direction of the weight. In U.S. Pat. No. 4,121,828, issued Oct. 24, 1978, to Amburgey and U.S. Pat. No. 4,183,527 issued Jan. 15, 1980, to Amburgey, as well, show indicia showing the central location of the gripping holes or vertical axis of the ball and indicia showing the plane of the stabilizing mass. Both of these patents teach two indicia on the surface of the ball and not how either are provided.
In U.S. Pat. No. 4,320,899, issued Mar. 23, 1982, to Salvino, an indicia is positioned on the surface of the ball to enable the drilling operator to locate the position the finger and thumb holes so as to intersect respective weight blocks. There is nothing taught as to how this indicia is provided and nothing to indicate providing center axis location of a weight block and the direction of a weight block itself.
Also, in U.S. Pat. No. 4,268,034 issued May 19, 1981, to MacDonald, an indicia of weight block is shown. However, the structure utilized provides an indicia element for the center of the weight block mass and a separate indicia element is positioned along the longitudinal axis of the weight block. Thus, the first indica locates the center of the weight block and the first with the second indicia locates the direction of the weight block.
Finally, it is known in the art to position bowling ball weight blocks in a parallel relationship to the rolling plane of the ball to provide dynamic stabilization. This is found in U.S. Pat. No. 4,121,828 issued Oct. 24, 1978 to Amburgey and U.S. Pat. No. 4,183,527 issued Jan. 15, 1980 to Amburgey, as well. Further, in U.S. Pat. No. 4,268,034 issued May 19, 1981 to MacDonald the weight block is placed either side of the ball for positive or negative side weighting. None of these drill the thumb and finger holes around the center axis of the weight block at a preselected angular relationship to a plane of symmetry to achieve a desired breaking point for the ball.